T-Killer, T-Helper Cells And Their Processes

Front 1

MHC Class II molecules interact with...

Back 1

CD4 Cells

Front 2

MHC Class I molecules interact with....

Back 2

CD8 Cells

Front 3

Which three signals are required for T-Cell activation?

Back 3

- Interactions of MHC/Peptide with receptor
- Cd4/Cd8 stabilising
- Co-stimulations

Front 4

Co-stimulatory Signals

Back 4

- CD28 receptor on T-Cells
- Interacts with CD80/CD86 (or B7) on APCs.

Front 5

Dendrites

Back 5

- Type of innate immune cell
- Long 'arms' increase S.A
- Phagocytose
- Stimulate T-Helper Cells
- Process MHC Class II
- Have lots of B7 molecules.

Front 6

Process of T-Cell Activation (From Dendritic Cells)

Back 6

- Langerhan's Cells (dendrites in epidermal layers of the skin)
- Sit in a 'mesh-like' network.
- Capture + pinocytose.
- Process MHC Class II molecules.
- Enter lymphatics and migrate to local lymph nodes.
- Enter lymph node and become trapped.
- Present MHC Class II to Naive T-Cells.
- If correct T-Cell present --> Activation (remember lots of B7)

Front 7

What happens after T-Cells are activated?

Back 7

Killers - will interact with MHC Class I and will undergo diapedesis and begin to kill infected cells.

Helpers:
- Begin to secrete IL-2 (promotes T-Cell growth) and this has causes nearby similar T Cells to divide and also itself) = CLONAL SELECTION

- Differentiate into T-Helper 1 or 2 Cells.

Front 8

T-Helper 1

Back 8

- Intracellular bacteria and virus infections
- Activation is by IL-12 (produced by phagocytes, dsRNA detection, CpG island detection)

Front 9

T-Helper 2

Back 9

- Extracellular toxins etc.
- Activation is by IL-4 (produced by Mast Cells)

Front 10

Cytokines of Th1

Back 10

IFN Gamma
TNF alpha
TNF beta
IL-2

Front 11

Cytokines of Th2

Back 11

IL-4
IL-5
IL-10

Front 12

IFN Gamma

Back 12

Macrophage Activation
Class I and II Processing
NK-Activation
Complement

Front 13

TNF Alpha

Back 13

Macrophage Activation
Extravasation

Front 14

TNF Beta

Back 14

Macrophage Activation
Neutrophil Activation
Tumor Killing

Front 15

IL-2

Back 15

T Cell Growth
CTL Activation